摘要：
SpringBoot实现的JPA封装了JPA的特性，而Repository封装了JPA的特性（正如我所理解的那样）。1.pom中引入了MySQL。xml和spring数据jpa依赖于它。2.创建应用程序。src/main/resource/下的属性配置文件，并配置数据库连接。3.在application.properties中配置jpa配置信息。4.编写实例热部署pom。xml配置
SpringBoot实现的JPA封装了JPA的特性, Repository是封装了jpa的特性(我是这么理解的)
1在pom.xml引入mysql, spring-data-jpa依赖
2.在src/main/resource/下新建applicatoin.properties配置文件，并配置数据库连接
3.在application.properties配置jpa配置信息
4.编写实例
热部署pom.xml配置
<!-- spring boot devtools 热部署 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
<scope>true</scope>
</dependency>
<!-- spring boot devtools的plugin --> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <!--fork : 如果没有该项配置，呢个devtools不会起作用，即应用不会restart --> <fork>true</fork> </configuration> </plugin>
1.加入依赖
<!-- mysql数据库驱动依赖 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- 添加spring-boot-data-jpa依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
2.applicaton.properties配置mysql
######################################################## ###datasource mysql ######################################################## spring.datasource.url = jdbc:mysql://localhost:3306/spring?useUnicode=true&characterEncoding=utf8 spring.datasource.username = root spring.datasource.password = spring.datasource.driverClassName = com.mysql.jdbc.Driver spring.datasource.max-active=20 spring.datasource.max-idle=8 spring.datasource.min-idle=8 spring.datasource.initial-size=10
3.配置jpa
######################################################## ### Java Persistence Api ######################################################## # Specify the DBMS spring.jpa.database = MYSQL # Show or not log for each sql query spring.jpa.show-sql = true # Hibernate ddl auto (create, create-drop, update) spring.jpa.hibernate.ddl-auto = update # Naming strategy #[org.hibernate.cfg.ImprovedNamingStrategy #org.hibernate.cfg.DefaultNamingStrategy] spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy # stripped before adding them to the entity manager) spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
4.测试实例：
Spring Boot JPA 总结
---------------------
1、需要添加相应的依赖包;
2、需要在application.properties文件添加配置信息；
3、需要创建一个实体类,比如Cat;
4、需要创建一个接口继承CrudRepository;
5、需要创建一个Service;
6、需要创建一个Controller;
7、代码测试；
cat.java
package com.muyang.boot1.demo.bean;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
/**
* 创建一个实体类
* 如何持久化
* 1.使用@Entity进行实体类的持久化操作,当JPA检测到我们的实体类中有@Entity的 注解的时候
* 会在数据库中生成对应的表结构
* 2.如何制定主键及生成策略
* 使用@id来生成主键
* @author Administrator
*
*/
@Entity
public class Cat {
/**
* 使用@Id生成主键
* 受用@GeneratedValue(strategy=GenerationType.AUTO)指定主键测策略，即mysql的自增Id
*/
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private int id;
private String catName;
private String catAge;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getCatName() {
return catName;
}
public void setCatName(String catName) {
this.catName = catName;
}
public String getCatAge() {
return catAge;
}
public void setCatAge(String catAge) {
this.catAge = catAge;
}
}
catRepository.java
package com.muyang.boot1.demo.repository;
import org.springframework.data.repository.CrudRepository;
import com.muyang.boot1.demo.bean.Cat;
public interface CatRepository extends CrudRepository<Cat, Integer> {
}
catService.java增删改查
package com.muyang.boot1.demo.service;
import javax.annotation.Resource;
import org.springframework.stereotype.Service;
import com.muyang.boot1.demo.bean.Cat;
import com.muyang.boot1.demo.repository.CatRepository;
@Service
public class CatService {
@Resource
private CatRepository catRepository;
/**
*
* update, save, delete操作
*/
//保存数据
public void save(Cat cat)
{
catRepository.save(cat);
}
//删除数据
public void delete(int id)
{
catRepository.delete(id);
}
//查询
public Iterable<Cat> getAll() {
return catRepository.findAll();
}
}
catController.java控制器
package com.muyang.boot1.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.muyang.boot1.demo.bean.Cat;
import com.muyang.boot1.demo.service.CatService;
@RestController
@RequestMapping("/cat")
public class CatController {
@Autowired
private CatService catService;
//增加
@RequestMapping(value="/add")
public String save()
{
Cat cat = new Cat();
cat.setCatName("大五");
cat.setCatAge("22");
catService.save(cat);
return "save ok.";
}
@RequestMapping("/del")
public String delete(int id)
{
catService.delete(id);
return "delete ok.";
}
@RequestMapping(value="/getAll", produces="application/json; charset=utf-8")
public Iterable<Cat> getAll()
{
return catService.getAll();
}
}
http://localhost:8080/cat/add
http://localhost:8080/cat/getAll